1. Technical Field
The present disclosure relates to implantable moldable biodegradable polymeric materials used in medicine for surgical repair.
2. Background of Related Art
Biodegradable materials are used in medicine for a variety of purposes including drug delivery devices and as aids in tissue repair. Physical and chemical properties of such materials can vary as in the case of different polymeric materials, e.g., melting point, degradation rate, stiffness, etc. The variability in physical and chemical properties allows products made from such materials to be tailored to suit specific applications.
Absorbable sutures can be made from biodegradable polymers such as glycolide and lactide. Biodegradable polymers can be used to coat sutures, e.g., U.S. Pat. No. 4,624,256 is directed to caprolactone polymers for suture coating. As described therein, the coating contains high molecular weight polycaprolactone or a high molecular weight copolymer of at least 90% by weight of caprolactone and at most 10% by weight of another biodegradable monomer such as glycolide and lactide. The high molecular weight polycaprolactone may be mixed with up to 50% by weight of lubricating agents which include poly(ethylene oxide).
A resorbable bone wax is described in U.S. Pat. No. 5,143,730. The bone wax is said to be suitable for mechanical staunching of blood on hard body tissue and is based on oligomers of glycolic acid and/or lactic acid with monofunctional and/or polyfunctional alcohols and/or corresponding carboxylic acids. A content of body-compatible salts of organic and/or inorganic acids is said to be formed by the reaction of any free carboxyl groups. Glycerol or glycerol partial esters are used to regulate the average molecular weight of the oligomer fraction.
U.S. Pat. No. 4,440,789 is directed to synthetic absorbable hemostatic composition. As described therein, a semisolid bone sealant contains between about 65% and 85% by weight of polydioxanone in a base which may contain ethylene/propylene oxide block copolymers, polyethylene glycols or methoxypolyethylene glycols. U.S. Pat. No. 5,080,665 is directed to a deformable absorbable surgical device manufactured from a block or graft copolymer. The copolymer is described as having a plurality of first linkages selected from the group consisting of glycolic acid ester and lactic acid ester linkages and a plurality of second linkages selected from the group consisting of 1,3 dioxane-2-one; 1,4-dioxane-2-one and .epsilon.-caprolactone linkages. A deformable surgical repair device is described as being manufactured from a blend of a first and second absorbable polymer, the first polymer corresponding to the first above linkages and the second polymer corresponding to the second above linkages.
Medical putty for tissue augmentation is described in U.S. Pat. No. 4,595,713 and is said to be useful in the regeneration of soft and hard connective tissue. As described therein, an implant material is composed of a copolymer of 60-95% epsilon caprolactone and 40-5% lactide. Catalysts used for the copolymer are metallic esters of carboxylic acids. The polymer is said to become moldable at hot water temperatures of about 115.degree.-160.degree. F.